Photon-assisted tunneling through a quantum dot at high microwave frequencies

Abstract

We investigate the influence of high frequency microwave radiation on single electron tunneling through a quantum dot. Effective coupling of the radiation to the quantum dot is achieved by an on-chip integrated broadband antenna. Simulations of the current distribution on the antenna are shown. We find that radiation with a frequency of ν=155 GHz, which corresponds to half of the bare charging energy Ec/2 results in an additional conductance peak within the Coulomb blockade regime. This additional resonance is attributed to photon-assisted tunneling.

Photon Assisted Tunneling in Quantum Dots

“…Structure due to photon energies below this value is washed out by the thermal energy k B T . The frequency scaling firmly establishes PAT as the transport mechanism [9,[11][12][13][14]. The observation that the sidebands move linearly with frequency, while the ground and excited state resonances stay fixed, supports our identification of the different peaks.…”

“…In 1993 PAT features were seen in the current-voltage characteristics of a GaAs/AlGaAs superlattice under THz irradiation from a free-electron laser [11]. Starting in 1994, PAT was also found in experiments on single-electron transport through semiconductor quantum dots [12][13][14][15][16]. The quantum dots in Ref.…”

Chaotic classical scattering and dynamics in oscillating 1-D potential wells

“…Clearly, if ǫ 0 ≥ 1 + 2η 1 then ǫ 1 ≥ 1 and the particle will certainly be transmitted with phase and energy given by Eq. (11) with N = 1. However, if ǫ 0 < 1 + 2η 1 , then ǫ 1 can be less than one, depending on the initial phase, and one cannot simply substitute φ N into ǫ N to determine the fate of the scattered particle, i.e., whether it was transmitted or reflected and with what energy.…”

“…Specifically, we consider the scattering of classical particles interacting with one and two 1D square wells with periodically oscillating depth. The square wells may represent the conduction band defined by a Al x Ga 1−x As − GaAs heterostructure or a quantum dot (see, e.g., [10], [11]) and the oscillating depth may represent the electron-phonon interaction [12] or the presence of a monochromatic elec-tromagnetic or acoustic field ( [4], [10], [13]). We will also consider the dynamics of a classical particle interacting with a chain of oscillating wells.…”

Nano-ploughed Josephson junctions as on-chip radiation sources

“…Then, the charge on the dot is allowed to fluctuate resulting in a sharp conductance peak due to tunneling of single electrons onto and off the dot. Photon-assisted tunneling under microwave irradiation leads to the occurence of photon-sidebands of these conductance peaks [33][34][35].…”